<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
		<title>本地图片预览</title>
		<style type="text/css">
			#preview {
				width: 100px;
				height: 100px;
				border: 1px solid #000;
				overflow: hidden;
			}
			#imghead {
				filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=image);
			}
		</style>
		<script type="text/javascript">
			function previewImage(file) {
				var MAXWIDTH = 100;
				var MAXHEIGHT = 100;
				var div = document.getElementById('preview');
				if (file.files && file.files[0]) {
					div.innerHTML = '<img id=imghead>';
					var img = document.getElementById('imghead');
					img.onload = function() {
						var rect = clacImgZoomParam(MAXWIDTH, MAXHEIGHT, img.offsetWidth, img.offsetHeight);
						img.width = rect.width;
						img.height = rect.height;
						img.style.marginLeft = rect.left + 'px';
						img.style.marginTop = rect.top + 'px';
					}
					var reader = new FileReader();
					reader.onload = function(evt) {
						img.src = evt.target.result;
					}
					reader.readAsDataURL(file.files[0]);
				} else {
					var sFilter = 'filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale,src="';
					file.select();
					var src = document.selection.createRange().text;
					div.innerHTML = '<img id=imghead>';
					var img = document.getElementById('imghead');
					img.filters.item('DXImageTransform.Microsoft.AlphaImageLoader').src = src;
					var rect = clacImgZoomParam(MAXWIDTH, MAXHEIGHT, img.offsetWidth, img.offsetHeight);
					status = ('rect:' + rect.top + ',' + rect.left + ',' + rect.width + ',' + rect.height);
					div.innerHTML = "<div id=divhead style='width:" + rect.width + "px;height:" + rect.height + "px;margin-top:" + rect.top + "px;margin-left:" + rect.left + "px;" + sFilter + src + "\"'></div>";
				}
			}

			function clacImgZoomParam(maxWidth, maxHeight, width, height) {
				var param = {
					top : 0,
					left : 0,
					width : width,
					height : height
				};
				if (width > maxWidth || height > maxHeight) {
					rateWidth = width / maxWidth;
					rateHeight = height / maxHeight;

					if (rateWidth > rateHeight) {
						param.width = maxWidth;
						param.height = Math.round(height / rateWidth);
					} else {
						param.width = Math.round(width / rateHeight);
						param.height = maxHeight;
					}
				}

				param.left = Math.round((maxWidth - param.width) / 2);
				param.top = Math.round((maxHeight - param.height) / 2);
				return param;
			}
		</script>
	</head>
	<body>
		<div id="preview">
			<img id="imghead" width=100 height=100 border=0 src='../images/head01_big.jpg'>
		</div>
		<br/>
		<input type="file" onchange="previewImage(this)" />
	</body>
</html>
